Hypodermic syringes are well-known in the prior art comprising: a cylindrical syringe body having a fluid-receiving chamber therein; a proximal end; and a distal end. The distal end of the syringe body tapers into a tip having a bore therethrough which communicates with the fluid-receiving chamber. The tip is covered with a closure means such as a stopper of a polymeric or elastomeric material, a tip cap or a membrane to prevent leakage and contamination of the fluid medication contained in the syringe barrel. The closure means must be able to be removed with relative ease when the prefilled syringe is to be used.
A plunger is inserted into the open proximal end of the syringe barrel for sliding in fluid-tight engagement with the inside wall of the fluid-receiving chamber. The plunger is equipped with a plunger rod to enable the user to exert pressure on the plunger.
The hypodermic syringe also includes a needle cannula, packaged separately from the syringe barrel, which has a proximal end attachable to the tip of the syringe barrel, and a distal end terminating in a sharp or blunt point. Some hypodermic syringes are equipped with a luer connector to be attached to a corresponding luer collar on the syringe barrel. Additionally, flexible tubing can be placed between the hypodermic syringe and a needle cannula with luer connectors at both ends.
It has been observed that during in-line processing, handling, and sterilizing of the prefilled barrels, some polymeric or elastomeric closures were missing from the tips of the barrels resulting in rejects. Also, during shipment of the finished product and handling by healthcare professionals some untipped barrels were observed which necessitated discarding of batches containing failed samples. For product integrity a corrective measure was indicated to prevent the polymeric or elastomeric closure from becoming dislodged from the tip of the barrel.
More importantly, it has also been recognized that untipped barrels, whether the damage occurred during shipment or handling, attracts the suspicion that the product was tampered with. Such possible tampering is a concern for both the National Regulating Authorities and the manufacturers who are required to insure safety, efficacy and the product integrity.
The prior art has provided various tamper evident closures for syringes.
One reference discloses a tamper evident syringe characterized in that the syringe barrel, the cap, and the plunger rod are covered with a tubular sealing device that is made from a heat-shrinkable film and which has been shrunk under heat so that it adheres closely to the surfaces of those members.
The sealing device comprises a tube and a tear tape. The tube is formed of a transparent heat-shrinkable film. The tear tape is attached by bonding to the inner surface of the tube from one end to the other in the longitudinal direction.
Another reference discloses a hypodermic syringe used with a needle for lyophilized medicament comprising: a syringe body having a piston therein equipped with a tip cap at its distal end; an elastomeric plug having a passage channel closing the neck of the syringe; and a protector cap which encloses the tip cap and the neck portion of the syringe body. The protector cap and tip cap are integral with each other and can be moved axially to open and close the syringe. The protector cap consists of a top portion and a bottom portion, the two parts being held together by a weakened portion. The center of the protector cap is provided with a small hole through which the tip cap can be viewed. In use, the top portion of the protector cap is snapped off at the weakened portion, and the tip cap is taken off and discarded. A needle is then fitted in the passage channel of the elastomeric plug to access the content of the syringe.
Still another reference discloses a syringe cap assembly placed on the distal end of a syringe. The assembly includes: an elastomeric insert having a passage therein; a retaining collar which fits over the elastomeric insert to hold the insert in place; a plug or tip cap is engaged in the insert to block the passage in the insert; and a retaining safety cap fitted over the tip cap. The end wall of the retaining safety cap is formed with a hole in its center and is slightly smaller in diameter than the plug so that the user can ascertain that the plug is properly in its place without opening the assembly.
In use the safety cap is pulled, twisted, and lifted off the assembly. The plug is then lifted off to expose the collar, and a needle assembly is fitted to the collar.
A further reference discloses a prefilled syringe with break-away tip seal which closes the passageway to the content of the syringe. A score means is provided adjacent to the tip for accommodating removal of the sealed tip.
An object of the present invention is to provide a prefilled tamper evident syringe or cartridge barrel which makes apparent the unauthorized use of the medical fluid contained in the barrel of the syringe or cartridge or at least warns healthcare professionals that such unauthorized use may have occurred.
The present invention also addresses the requirement of tailor-making the barrel to provide various degrees of protection against tampering, i.e. certain medical fluids, such as narcotics, lends a grater incentive for tampering than other medical fluids, such as a saline solution. To wit, a barrel containing narcotics should have more than one built-in tamper evidence, although such an approach can equally apply to other medicaments.
Another object of the present invention is to provide tamper evident syringe or cartridge barrels the content of which is easily accessed by the healthcare professionals while their unauthorized use is readily apparent.
A further object of the present invention is to provide a tamper evident syringe or cartridge barrel the content of which can be accessed by luer connections or a tubing conduit so as to avoid the use of “sharps” and thereby preventing needle stick injuries.